Refrigerating process and apparatus



'Oct. 21 1924.

I. POTTER REFRIGBRATING PROCESS AND APPARATUS Filed Sept. 15 1921 Patented Oct. 21

UNITE THOMAS IRVING POTTER, OF EAST ORAN D STATES I 1,512,133 PATENT. OFFICE.

GE, NEW JERSEY, ASSIGNOR TO FEDERATED ENGINEERS DEVELOPMENT CORPORATION, OF JERSEY CITY, NEW JERSEY, A. COR- IORATIO'N OF DELAWARE.

REFRIGERATING PROCESS AND APPARATUS.

Application filed September 15, 1921. Serial No. 500,756.

T 0 all whom it may concern:

Be 1t known that I. THOMAS IRVING Po'r- TER, a citizen of the United States, residing at East Orange. in the county of Essex and State of New Jersey, have lnvented certain new and useful Improvements 1n Refrlghereby declare the clear, and reference drawing, forming a Apparatus: and I do following to be a full,

exact description of the same, being had to the accompanying part of this specification.

This invention relates to refrigerating apparatus "particularly adapted for the use of ethyl chloride although as will as a refrigerating agent be obv1ous other known refrigerating agents may be used in the apparatus adopted for purposes of illustration in the present instance. A

One object of the invention is to provide an apparatus for refrigerating havmg a capacity suitable for use in dwellings, the

apparatus being of simple construction and not requiring skilled attention to keep it in proper working order.

A further object necessity of employing is to dis ense with the heatmg means for vaporization purposes during the operation of the apparatus.

The invention contemplates the provision of a refrigerating pression type, the

apparatus of the comoperation of Which is automatically controlled by the difference in the pressures acting upon opposite sides of themeans for exhausting refrigerant from the low pressure side of the machine.

The particular embodiment of the invention shown discloses an apparatus in which such pressures are identical with the pressures existent on the high and low pressure sides of the machine, but the invention in its broadest form is not thus limited, since the use of other pressures to control the operation of the apparatus is shown in my co-pending application,

filed September 12,

Serial No. 587,698, 1922,

Withthese and other objects in view, the 1nvent1on consists 1n certa1n improved arrangements and combinatlons of parts all as will be out particularly in the In the accompanying hereinafter described and pointed appended claims.

is an assembled elevational view, partly in section, showing th ferred form.

e apparatus in its predrawing the figure Generally, the invention comprises a motor operated pump for exhausting a vaporized refrigerating agent from the refrigerating chamber and returning the vapors through a condenser, where they are liquefied, to the refrigerating chamber. In the preferred form of apparatus the pump is of the double acting type with each of its chambers or cylinders in communication with both the refrigerating chamber and the condenser and condenser reservoir, there being -suitable check valves interposed in the connections whereby the cylinders of the pump, when expanded will exhaust vapors from the refrigerating chamber and when contracted will force the vapors back to the condenser.

In assembling the apparatus, the motor and pump together with the condenser ,are preferably mounted on a base plate 1 having four upright supporting posts 2 arranged. thereon in circular formation. The pump is preferably of the bellows type, the end walls of its chamber or cylinders being formed by vertically spaced circular plates 4, 4c fixedly secured on the posts 2. To permit expansion and contraction of the pump chambers the side Walls of the latter are of bellows pattern, expansible members 9' being secured in sealed union to the end plates 4 and a plate 5 slidably mounted on posts 2 intermediate plates 4 and serving as the plunger of the pump.

While any desired type of motor may be utilized for imparting a reciprocatory motion to the plunger 5" of the pump, it is preferred that the motor be constructed similarly to the pump, the end Walls of the motor cylinders being formed by plates 3 secured on the posts 2 and the piston formed by a plate 5 slidable on said posts intermediate the plates 3. The cylinders of the motor are also ada ted to be expanded and contracted, expansible members 9 forming the sides of the cylinders being secure to the plates 3 and 5. Piston 5 of the motor and plunger 5 of the pump are rigidly connected together by rods 6, 7 and motion imparted to piston 5 will consequently be transmitted to the plunger 5*. lWater is supplied to the expansible cylinders of the motor by pipe connections 10, 11 from a pipe 18 connected to the usual service pipe. To control the delivery of water alternately to the chambers of the motor, a double acting piston valve 12 is interposed between pipe 18 and pipes 10, 11, the latter pipes communicating with ports 14, 13, respectively, in said valve. The ports are controlled by pistons 16, 15 mounted on a piston rod 17 operated by mechanism hereinafter described to alternately place ports 14, 13 in communication with pipe 18 and in communication with channels 19 in valve 12 leading to the discharge pipe 20 of said valve. W'ater 'previously supplied to one side of the motor piston will, on the return stroke of the piston, be returned to the channels 19 in valve 12 and discharged through the pipe 20 into the bottom of a condenser chamber 21 formed by a casing 22 having an opening 23 therein for the final discharge of the water from the apparatus.

Communicatin with the interiors of the expansible cham ers of the pump are two pipes 24, 24 having outlet check valves 25 therein. Pipe 24 extendsup into the lower pump chamber, its upper end being positi'oned adjacent the pum plunger 5 when the latter is in its lowermost position. Pipes 24, 24 join in a pipe 26 which terminates in a condensing coil 27 in the condensing chamber 21. As will hereinafter appear, the vaporized refrigerating agent is pumped through the condenser coil 27 to the condenser reservoir 28 from where it is supplied in liquid form through a pipe 34th the refrigerating chamber 32- which may be located at any desired point, for instance within an ice box 33. Pipe 34 communicates with a pipe 35 extendin into the interiorof the refrigerating chamber 32 and to regulate the supply of refrigerating agent to said chamber the inner end of pipe 35 is adapted to be opened and closed by a needle valve 36 on a lever 37 having one end pivoted at 36' and provided at its opposite end with a float 38.

As the refrigerating agent in chamber '32 is vaporized, to abstract heat from the surrounding chambers, the vapors are exhausted from the refrigerating chamber by the pump through'a pipe 31 havin branches 29 eadmg into the pump cham ers, each of said branches having a check valve 30 therein to prevent the return of the vapors from the umpto the refrigerating chamber.

The mechanism for I'QCiPIOOfl-tlll piston rod 17 of valve 12 preferably consists of a lever 40 pivotally secured by a pin 39 to a cross rod 8 carried by the connecting rods 7 whose upper ends project above the upper plate 4 of the pump. Lever 40 is fulcrumed at one end by a pin and slot connection 42, 43 in a standard 44 on top plate 4' and its opposite end is attached to the upper end of piston rod. 17 by a loose or pln and'slot connection 45, 46, the pin and. slot connections permitting lost motion for a purpose to presently appear. Projecting from the lower plate 4 is an extension, 47 having pivoted thereon a lever 48 provided at its upper end with a V-shaped cam surface 49 adapted to be yieldingly held in contact with a cam roller 50 on lever 40 by a spring 51 anchored to upper plate 4.

In operation, the chambers or cylinders of the pump are practically filled with a heavy oil or other suitable inert liquid and the re frigerating chamber 32 is filled with any suitable refrigerating liquid, preferably ethyl chloride, to a height sufficient to support the float 38 in a position where valve 36 will close pipe 35 against the normal pressure existing in said pipe. The reservoir 28 ment of the pump plunger is upward (water having been supplied to the under side of motor piston 5 through port 14 and pipe 10) lever 40 will be elevated and the cam roller 50 will push lever 48 to the right until the roller passes the point of the V-shaped cam surface, 49 when spring 51 tending toreturn lever 48 to the left will pull said lever back and the upper portion of cam 49 bearing against roller 50 will suddenly elevate lever 40 and the piston 17 of valve 12. Piston 17 is not moved during the movement of lever 48 to the right, any upward movement of lever 40 during that period being compensated for by the pin and slot connection 45, 46. This movement of the piston 17 will permit water to be supplied to the upper side ofmotor piston 5 and depress the latter, the previous charge of water being exhausted from the lower motor cylinder through port 14, channel 19 in valve 12 and pipe 20 to the condenser chamber. The

movement of pump plunger 5 is also re-. versed, the upper chamber of the pump being expanded to exhaust vapors from chamber 32 while the vapors previousl exhausted are pumped back to the con enser and reservoir. This alternate movement of the pump plunger upward and downward is continuous during evaporatipn of the liquid in chamber 32. the refrigerating agent being gradually drawn off from the refrigerating chamber until valve 36 is opened, when additional liquid will be supplied from reservoir 28 by the pressure created in the reservoir by the pump. It will be obvious that the vaporization of the refrigerating liquid will abstract heat from compartment 33.

A pressure regulating valve 18 is interposed in the supply pipe 18 permitting delivery of the motive fluid to the motor at any desired pressure. As the motor is operated, the pump piston 5 acts to reduce the pressure in the evaporator (low pressure side) by exhausting the vaporized refrigerant therefrom. At the same time, compressed, saturated vapor is forced into the condenser (high pressure side) whereby a pressure which is equivalent at least to atmospherlc is maintained in the high pressure side of the apparatus. As the temperature of the medium surrounding the evaporator is gradually lowered, the rate of vaporization of the liquid in the evaporator will decrease. This will operate to increase the difference in the pressures acting upon opposite sides of the pump piston. thereby creating a back pressure on the pump piston which tends to resist and retard operation of the same. When the temperature of the evaporator has been sufficiently lowered, this pressure difference will be great enough to counterbalance and render inoperative the pump actuating means. The operation of the pump will thereby be stopped until such time as the 1 of the evaporator again rises. When such increase in temperature occurs, operation will be automatically resumed as will be readily understood. The adjustment of the'valve 18 to regulate the force acting on the pump governs the temperature to which the evaporator must be reduced in order to stop the machine. Such temperature regulation will be found accurate enough for all ordinary domestic purposes.

It is to be borne in mind that the difference in pressure between the high and low sides of the machine does not in any way effect the operation of the valve 36. This valve is strictly float-controlled to maintain a predetermined liquid level in tor.

What is claimed is:

1. In a refrigerating apparatus, the combination with a compressor, condenser and expander arranged in a closed refrigerating circuit, said compressor adapted to exhaust vaporized refrigerant from the expander and deliver the same at increased pressure to the condenser, of means for maintaining a constant level of liquid refrigerant in the expander whereby a suflicient reduction in the rate of vaporization of the liquid refrigerant in the expander causes a difference in pressureupon opposite sides of said exhausting and delivering means which resists and counterbalances the power used in operating the same. 1

2. In a refrigerating apparatus, the combination with a compressor, condenser and expander arranged in a closed refrigerating temperature circuit, and said compressor including means for exhausting vaporized refrigerant from v the expander and delivering the same at into the expander,

the evaporacreased pressure to the condenser, of a pressure motor for operating the compressor, manually operable means for regulating the pressure under which said motor operates and means independent of the pressures In I the expander and condenser for controlling the flow of refrigerant from the condenser whereby upon the creation of a sufficient difference in pressure between the high and apparatus, a counterbalancing back pressure is created to resist and stop the motor.

3. In a refrigerating apparatus, the combination with a compressor, condenser and expander arranged in a closed refrigerating circuit, and said compressor including means for exhausting vaporized refrigerant from the expander and delivering the same at increased pressure to the condenser, of a motor for operating the expander, means under manual control for regulating "the power under which the motor is operated, means independent of the pressures in and condenser for controlling the flow of refrigerant from the condenser to the exrander, whereby upon the creation of a. sufficient difference in pressure between the high and low sides of the apparatus a counterbalancing back pressure 1s created to resist and stop the motor.

4;. In a refrigerating apparatus, the combination with a compressor, condenser and expander arranged in a closed refrigerating circuit, and said compressor including means for exhausting vaporized refrigerant from the expander and. delivering the same at increased pressure to the condenser, of means for manually regulating the power under which the compressor is operated, means independent of the difference in pressures on the high and low sides of the apparatus for controlling the flow of liquid refrigerant from the condenser to the expander, said means being adapted to prevent any flow therebetween when the rate of vaporization of the refrigerant in the expander has been reduced to a predetermined point.

5. In a refrigeratlng apparatus, a compresser condenser and expander arranged in a closed circuit, said compressor being operated by fluid pressure to exhaust vapo-' low pressure sides of the the expander circuit, said compressor including means for exhausting vaporized refrigerant from the expander and delivering the same at increased pressure to the condenser, of a fluid motor operating at a predetermined and substantially constant pressure for actuating the compressor, said motor being adapted to be resisted and counterbalanced when the difference in the pressures upon opposite sides of said exhausting and delivering means has reached a predetermined point, and means independent of such pressure difl'erence for controlling the flow of refrigerant from the condenser to the expander.

7. In a refrigerating apparatus, the combination with a compressor, condenser and expander arranged in a closed refrigerating circuit, and said compressor including means for exhausting vaporized refrigerant from the expander and delivering the same at increased pressure to the condenser, of a float valve for maintaining a constant level of liquid refrigerant in the expander and manually operable means for controlling the power used in operating the compressor.

8. In a refrigerating apparatus, the combination with a compressor, condensor and expander arranged in a closed refrigerating circuit, and said compressor including means for exhausting vaporized refrigerant from the expander and delivering the same at increased pressure to the condenser, of a motor for operating the compressor, said motor adapted to be resisted and counterbalanced when the differences in the pressures upon opposite sides of the compresser have reached a predetermined point,'and means independent of such pressures for controlling the flow of refrigerant from the high to the low pressure sides of the apparatus. 9. A method of refrigeration which consists in evaporating a volatile working fluid .volatile working fluid in said chamber, me-

chanically exhausting the vaporized fluid from the chamber, mechanically compressing the fluid exhausted from the cooling chamber, and utilizing the braking action of the working fluid on the compressor to stop the compressor whenever the temperature within the cooling chamber has been reduced to a predetermined point.

11. A method of refrigeration which consists in evaporating a working fluid in a cooling chamber, exhausting the vapor, mechanically compressing the vapor, condensing the compressed vapor, returning the liquefied working fluid to the cooling chamber, controlling the return of condensed fluid to the cooling chamber by the unevaporated fluid in the cooling chamber, and stalling the compressor by the direct fluid braking action of the working fluid whenever the temperature of the cooling chamber has been reduced to a predetermined oint.

THOMAS IRVING P TTE-R. 

